Isocyanate fluorous-tagged

The described fluorous-tag strategy has also been applied to the synthesis of biaryl-substituted hydantoins (Scheme 7.81) [94]. 4-Hydroxybenzaldehyde was converted into the corresponding perfluorinated species, which was then subjected to a reductive amination. The resulting amine was treated with an isocyanate to produce the fluorous-tagged urea, which spontaneously cyclized to form the corresponding hydantoin. Finally, the fluorous tag was detached by a Suzuki-type carbon-carbon bond formation to furnish the desired target structure in good yield. 

Zhang and coworkers have developed the use of fluorous-tagged isocyanate as well as isatoic anhydride and acid chloride for the scavenging of amines for use in combinatorial as well as conventional chemistry (Figure 8.3) [30]. All reagents were readily prepared from commercially available sources, and the F-isatoic anhydride was prepared via a simple NaH-mediated alkylation of isatoic anhydride with per-fluoroalkyl halide. 

Figure 8.3 Fluorous-tagged isocyanate, isatoic anhydride and acid chloride for the scavenging of amines.

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